Transmission device for an air compressor

ABSTRACT

A transmission device for use in an air compressor includes a first gear connectable to the motor shaft, a second gear connectable to the compressor shaft and a gear assembly provided with a third gear mated with the first gear and a fourth gear mated with the second gear so that rotation of the motor shaft drives the first gear to rotate, which drives the third gear and the fourth gear to rotate and thus the compressor shaft is rotated.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a transmission device, and more particularly to a transmission device for an air compressor to effectively transmit power from the motor to the air blower and to reduce volume of the air compressor.

2. Description of Related Art

With reference to FIG. 4, a conventional air compressor includes a motor (50) with a first wheel (51) securely connected to the motor (50) and a compressor (53) with a second wheel (54) securely connected to the compressor (53). A belt (52) is mounted around the first wheel (51) and the second wheel (54). Therefore, when the motor (51) is activated, the second wheel (54) is driven by the belt (52) to rotate. Accordingly, the compressor (53) is rotated and air inside an air tank (60) is compressed.

It is noted from the drawing that when the power from the motor (50) is to be transmitted, a motor shaft (not shown) is extending latitudinally to a longitudinal axis of the air tank (60) and a compressor shaft (not shown) is also extending latitudinally to the longitudinal axis of the air tank (60), such that the overall dimension of the air compressor is bulky. Furthermore, the belt (52) interconnected between the first wheel (51) and the second wheel (54) is easily worn and has elasticity fatigue. Therefore, the power transmission effect from the motor (50) to the compressor (53) is not as good as expected, constant replacement of the belt (52) is inevitable.

To overcome the shortcomings, the present invention tends to provide an improved transmission device to mitigate the aforementioned problems.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide an improved transmission device mounted between the motor and the compressor to directly transmit power from the motor to the compressor without worry about elasticity fatigue.

Another objective of the present invention is to provide an improved transmission device which is able to effectively reduce dimension of the air compressor so that the air compressor with the transmission device of the present invention installed therein is compact.

Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic side plan view showing that a gear box is mounted between the motor and the compressor;

FIG. 2 is a cross sectional view showing the inner structure of the gear box between the motor and the compressor;

FIG. 3 is a side plan view of the air compressor having the transmission device of the present invention installed therein so that the dimension of the air compressor is compact; and

FIG. 4 is a schematic side plan view of a conventional air compressor.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference to FIG. 1, an air compressor in accordance with the present invention includes a motor (10), a compressor (20), a gear box (30) sandwiched between the motor (10) and the compressor (20). Furthermore, an air tank (40) is mounted under the motor (10) and the compressor (20) and communicated with the compressor (20).

The gear box (30) has a first housing (31) facing to the motor (10) and a second housing (32) facing to the compressor (20) and integrally formed with the first housing (31) by any appropriate method known in the art, i.e. welding or bolting. The first housing (31) has a first gear (33) to be mated with a distal end of the motor shaft (11) and the second housing (32) has a second gear (34) to be mated with a distal end of the compressor shaft (21). First bearings (331) are provided at the joint between the motor shaft (11) and the first gear (33) and second bearings (341) are provided at the joint between the compressor shaft (21) and the second gear (34) so that the positioning between the motor shaft (11) and the first gear (33) and between the compressor shaft (21) and the second gear (34) is secured. A sleeve (35) is rotatably provided inside the first housing (31) and the second housing (32) and has therein a gear assembly (36) provided with a third gear (361) mated with the first gear (33) and a fourth gear (362) mated with the second gear (34).

When the air compressor of the present invention is in use, the motor shaft (11) drives the first gear (33) to rotate, which drives the gear assembly (36) to rotate. Due to the rotation of the gear assembly (36), the rotation of the fourth gear (362) drives the second gear (34) to rotate. Accordingly, the compressor shaft (21) mated with the second gear (34) is driven to rotate.

With reference to FIG. 3, it is appreciated that between the motor shaft (11) and the compressor shaft (21) are in line with one another, which are horizontal to a longitudinal axis of the air tank (40) of the air compressor, the air compressor dimension is reduced.

It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

1. In an air compressor having a motor having a motor shaft, a compressor driven by the motor via a transmission device and having a compressor shaft and an air tank mounted under the motor and the compressor to communicate with the compressor, wherein the improvement comprises: the transmission device having a first gear connectable to the motor shaft, a second gear connectable to the compressor shaft and a gear assembly provided with a third gear mated with the first gear and a fourth gear mated with the second gear so that rotation of the motor shaft drives the first gear to rotate, which drives the third gear and the fourth gear to rotate and thus the compressor shaft is rotated.
 2. The air compressor as claimed in claim 1, wherein a gear box adapted to be mounted between the motor and the compressor includes a first housing facing to the motor and a second housing facing to the compressor and integrally formed with the first housing.
 3. The air compressor as claimed in claim 2, wherein a sleeve is mounted between the first housing and the second housing to enclose therein the gear assembly.
 4. The air compressor as claimed in claim 3, wherein first bearings are mounted at a joint between the motor shaft and the first gear and second bearings are mounted at a joint between the compressor shaft and the second gear. 